US2579248A

US2579248A - Sewing machine

Info

Publication number: US2579248A
Application number: US722814A
Authority: US
Inventors: Austlid Arnljot
Original assignee: Individual
Current assignee: Individual
Priority date: 1946-01-22
Filing date: 1947-01-18
Publication date: 1951-12-18
Anticipated expiration: 1968-12-18
Also published as: GB620548A; FR939872A; CH260062A; BE470686A; DE839751C

Description

A. AUSTLID 2,579,248

SEWING MACHINE Filed Jn. 18, 1947 Dec. 18, 1951 Patented Dec. 18, 1951 SEWING MACHINE Arnljot Austlid, Oslo, Norway Application January 18, 1947, Serial No. 722,814 In Norway `llanuary 22, 1946 Claims.

This invention relates to sewing machines adapted for making zig-zag-seams.

The machine in question is of the type in which the needle bar and the looper shaft thereof are interconnected by a displaceable bail or the like adapted to be reciprocated in the longitudinal direction of the machine, thus transferring the same movements to the needle bar and to the looper shaft, whereby zigzag-seams may be made.

It is an object of the invention to provide for such interconnection of the needle bar, the ball and the looper shaft that said bar and shaft will be displaced absolutely in unison in the 1ongitudinal direction of the machine.

Another object is to provide a simple but effective driving arrangement for said bail, which arrangement is adjustable in a simple manner, so as to set the bail for zigzag-seams of different widths or for usual straight seam if desired.

Other features of the invention are disclosed in and by the following description.

The annexed drawing illustrates an embodiment of the invention, where only those parts of the machine which relate to the invention are shown.

Figure 1 is a side View of a sewing machine according to the invention, part of the front being broken away, to show certain features of the mechanism.

Figure 2 is an end view of the same, also with a part broken away.

Figure 3 shows, on a larger scale, a detail of the mechanism.

The sewing machine body consists of the arm I with head and supporting standard, and of the base plate 2 of channel-formed section. Withinthe base plate is journalled a looper shaft d, driven by a motor or in other suitable manner, and carrying a looper 5, which is located beneath the needle bar 3 and 4cooperates with the needle. When the machine is to be used for sewing zigzag-seams the needle bar 3 and the looper shaft 4 with its looper 5 must reciprocate synchronously in the longitudinal direction of the machine, and the needle must be moved down into the fabric each time the needle bar and the looper are at one of the end positions of their reciprocating movements.

Intercoupling of needle bar and looper shaft is obtained by means of a bail E-, reciprocally housed in the machine arm i. At one end of said bail is directly journalled the needle bar 3, and the other end of the bail directly carries the looper shaft 5, which is rotatable but not displaceable therein. More specifically, the bail 6 has an enlarged end portion 6 in which the needle bar 3 is slidably mounted for vertical movement. The drive means for reciprocating the needle bar vertically is omitted as superfluous, being understood in the art, and forming no actual part of the invention. On the other hand, the downwardly projecting portion 6" of bail 6 may be provided with a hole in which looper shaft 4 is rotatably mounted, thus the bail and looper shaft are movably connected together and associated. In order to prevent undesired axial movement of this looper shaft relatively to the bail, the bail portion 5" is located between two shoulders or flanges 2S fixed on the looper shaft. Thus, when the bail 6 is reciprocated in the longitudinal direction of the machine, the needle bar and the looper shaft both must move exactly in the same manner.

The bail 6 receives its reciprocating movement from a crank 8 on a shaft I rotated by the machines driving mechanism. The latter includes the gear 25 which meshes with and is driven by pinion 2t on the end of looper shaft 4. The length of pinion 2S is, of course selected to be sufficient to allow the pinion to slide along in parallelism to the axis of gear 25 during longitudinal displacement of looper shaft 4. In order to facilitate axial movement of the looper shaft, the rotor of the driving motor 21 is axially movable a short distance corresponding to the eX- tent of the axial movement of the mentioned looper shaft which is secured to the rotor. 'I'he connecting rod 9 of the crank is pivotally attached to an arm II, between the ends thereof. by means of a pin I0. At one end thereof said arm Il is by means of a pin I2 pivoted on the vertical part of the bail 6, and the other end of arm II carries a follower roller I3, engaged in a cam groove I4 provided in a guide member I5', which for instance may be cylindrical. This guide member I5 is secured to a shaft I5, which may be adjusted into different angular positions by means of an arm I1, whereby the groove I4 may be set in different angular positions.

The arrangement described operates as follows: When the crank 8 rotates the follower roller I3 is displaced in and guided by the cam groove I4, and if the latter is set in an oblique or sloping position, for instance as shown in Figure 1, roller I3 must reciprocate a little in horizontal direction, arm I I simultaneously being raised and lowered, swinging on its pivot I2. This reciprocating movement of roller I3 is, through arm I I and pivot I2, transferred to the bail 6, which latter thereby causes the needle bar and the looper shaft to reciprocate accordingly. By turning shaft IS by means of arm II the guide member I5 with groove I4 may be set in any desired angular position, thus adjusting the extent of the reciprocating movement and thereby the width of the zigzag-seam. When groove I4 is set in vertical position no reciprocating movement of bail 6 occurs, and the machine will sew an ordinary, straight seam. In order that no movement at all shall be imparted to bail 6- when the groove is in this position, the major intermediate portion of the groove is formed with a circular curve having its center of curvature in the axis of pivot I2, the roller I3 then exerting no pressure on the walls of the groove when arm I I is raised and lowered.

In order to enable the seam to be shifted to the right or to the left without shifting the piece of fabric, shaft IG is eccentrically journalled in a sleeve I8, which latter is rotatably supported in the front material of the machine body and adapted to be set in different angular positions by means of an arm ZIJ. Turning of sleeve I 8 causes shifting of shaft I6 and thus also of guide member I5 towards the left or towards the right, and such shifting is, through arm I'I and bail 6, transferred to the needle bar and to the looper shaft.

Figure 3 shows a section through the guide member I5 with groove I4 and the roller I3, on a larger scale.

The fabric mover or feeder 2I is driven from a shaft 22. Said shaft carries two

eccentric portions

23 and 24 respectively, which are coupled to the fabric mover by means of arms, so

that the fabric mover receives a vertical and also a horizontal reciprocating movement. Control of the stitch-length and also reversion of the direction of movement of the fabric is effected by means of a controlling arm, in a manner known per se. However, in accordance with the invention said control mechanism is so arranged, that the fabric mover is automatically lowered if the stitch-length is adjusted to become zero, and is again raised if the stitch-length is increased.

Preferably the looper shaft 4 is provided with an extension 28 penetrating the material of the machine body and adapted for attachment of a pool member when thread should be spooled.

The constructional details of the arrangement shown may be widely modined and varied within the scope of the invention.

I claim:

l. In a zig-zag stitch forming sewing machine comprising a base; a machine body on said base; and a horizontal looper shaft mounted in said base for recipr-ocation in a horizontal direction, the combination of a'needle bar arranged partly within the machine body and depending toward said base; an elongated bail located within said machine body having an integral depending portion projecting into said base and mounted for horizontal reciprocation; an enlarged end portion upon the elongated bail in which the needle bar is slidably mounted for vertical movement, the depending portion of said bail having a bearing hole for supporting said looper shaft in order to allow the latter to extend through said bail; means upon said looper shaft engaging with said bail at both ends of the bearing hole therein for preventing axial displacement of said looper shaft with respect to said bail; and operating means for reciprocating said bail in the horizontal direction and thereby oscillating the bail together with said needle bar and said looper shaft.

2. In a zig-zag stitch forming sewing machine comprising a base; a substantially L-shaped hollow machine body having a longer horizontally extending body portion and a relatively shorter vertically extending body portion, the combination of a looper shaft mounted in said base reciprocably in a horizontal direction parallel to the longer body portion of said L-shaped machine body; a needle bar slidably mounted for vertical movement at the free end of said horizontally extending longer body portion of said L-shaped machine body; a substantially elongated bail having a longer bail portion and a relatively shorter bail portion, said bail being so disposed within said machine body that said longer bail portion is located within said longer body portion and said shorter bail portion is located within said short body portion and depending into said base; means including an enlarged free end portion upon the longer bail portion for supporting the needle bar for vertical sliding movement, the short end of said bail having a bearing hole through which the looper shaft extends means upon said looper shaft engaging with said bail at both ends of the bearing hole therein for preventing aXial displacement of said looper shaft with respect to said bail; and means for reciprocating said L-shaped bail in a horizontal direction and thereby oscillating the bail together with said needle bar and said looper shaft.

3. In a zig-zag stitch forming. sewing machine comprising a base; a machine body on said base; a horizontal looper shaft mounted in said base for reciprocation in a horizontal direction, the combination of a needle bar arranged partly within the machine body and depending toward said base; an elongated bail located within said machine body having an integral depending portion projecting into said base and mounted for horizontal reciprocation; an enlarged end portion uponthe elongated bail in which the needle bar is slidably mounted for vertical movement, the depending portion of said bail having a bearing hole for supporting said looper shaft in order to allow the latter to extend through said bail; means upon said looper shaft engaging with said bail at both ends of the bearing hole therein for preventing axial displacement of said looper shaft with respect to said bail; and operating means for reciprocating said bail in the horizontal direction and thereby oscillating the bail together with said needle bar and said looper shaft; said operating means including an arm disposed transversely of the depending portion of said bail; an angularly adjustable guide member; a crank with a connecting rod pivotally connected to the intermediate portion of said arm and the latter arm at the ends thereof being respectively pivotally connected to said bail and operatively in contact with said angularly adjustable guide member, the guide member having guide means of such construction for guiding said arm that horizontal movements are transferred to said arm and to the bail upon rotation of said crank.

4. In a zig-zag stitch forming sewing machine comprising a base; a machine body on said base; a horizontal looper shaft mounted on said base for reciprocation in horizontal direction, the combination of a needle bar arranged partly within the machine body and depending toward said base; an elongated bail located within said machine body having an integral depending portion projecting 'into said base and mounted for horizontal reciprocation; an enlarged end portion upon the elongated bail in which the needle bar is slidably mounted for vertical movement, the depending portion of said bail having a bearing hole for supporting said looper shaft in order to allow the latter to extend through said bail; means upon /said looper shaft engaging With said bail at both ends of the bearing hole therein for preventing axial displacement of said looper shaft with respect to said bail and operating means for reciprocating said bail in the horizontal direction and thereby oscillating the bail together with said needle bar and said looper shaft; said operating means including an arm disposed transversely of the depending portion of said bail; an angularly adjustable guide member; a crank With a connecting rod pivotally connected to the intermediate portion of said arm and the latter arm at one end thereof operatively engaging with said bail, the angularly adjustable guide member having a curvilinear cam groove; and a follower rotatably mounted at the other end of said arm and engagin-g in said curvilinear cam groove, at least the major intermediate portion of the curvilinear cam groove having a radius substantially equal to the length of said arm.

5. In a zig-zag stitch-forming sewing machine comprising a base; a machine body on said base; and a horizontal looper shaft mounted onsaid base for reciprocation in horizontal direction, the combination of a needle bar arranged partly Within the machine body and depending toward said base; an elongated bail located Within said machine body having an integral depending portion projecting into said base and mounted for horizontal reciprocation; an enlarged end portion upon the elongated bail in which the needle bar is slidably mounted for vertical movement, the depending portion of said bail having a bearing hole for supporting said looper shaft in order to allow the latter to extend through said bail;

means upon said looper shaft engaging with said bail at both ends of the bearing hole therein for preventing axial displacement of said looper shaft with respect to said bail; and operating means for reciprocating said bail in horizontal direction and thereby oscillating the bail together With said needle bar and said looper shaft, said operating means including an arm disposed transversely of the depending portion of said bail; an'angularly adjustable guide member, a crank with a connecting rod pivotally connected to the intermediate portion of said arm and the latter arm at one end thereof operatively engaging with said bail, the angularly adjustable guide member having a curvilinear cam groove; a follower roller rotatably mounted at the other end of said arm and engaging in said curvilinear cam groove, at least the major intermediate portion of the curvilinear cam groove having a radius substantially equal to the length of said arm; a rotatably adjustable sleeve mounted in said machine body and having an eccentric bearing hole therein; and a shaft rotatably mounted in the eccentric bearing hole in said rotatably adjustable sleeve and rigidly secured at one end thereof to said guide member.

ARNLJOT AUSTLID.

REFERENCES CITED The following references are vof record in the le of this patent:

UNITED STATES PATENTS Number Name Date 1,232,263 Finch July 3, 1917 2,045,340 Bolter June 23, 1936 FOREIGN PATENTS Number Country Date 421,357 Germany Nov. 10, 1925